Applies to:
Indoor (Ducted): ARTH09KSLAP / ARTH12KSLAP / ARTH18KSLAP
Outdoor (Single type): AOTH09KBTA / AOTH12KBTA / AOTH18KBTA
Controllers: Wired Remote Controller or Wireless Remote Controller (optional, job-dependent)
Refrigerant: R32
Audience: Authorised service personnel / professional installers

Contents

1) Safety and compliance

  • Installation and servicing must be completed by qualified and experienced personnel only.
  • Do not energise the system until all installation work is complete and covers are fitted.
  • After isolating power, wait before touching electrical components (observe manufacturer discharge guidance).
  • If refrigerant leakage occurs during works: ventilate immediately, remove ignition sources, and do not use open flame detection methods.
  • Use vacuum pump evacuation (do not purge with refrigerant).
  • Ensure correct grounding/earthing and earth leakage protection as required by local regulations.
  • Keep piping sealed during handling to prevent moisture ingress and contamination.

2) R32 refrigerant requirements

  • R32 operates at higher pressures than legacy refrigerants; only use R32/R410A-rated tools, hoses and materials.
  • Charging port thread for R32/R410A: 1/2–20 UNF.
  • Leak detection must be suitable for flammable refrigerants; do not use open flame methods.
  • Prevent moisture/foreign matter entering piping; seal pipe ends during storage/handling.
  • Comply with relevant safety standards and local regulations for flammable refrigerants.

2.1 Minimum installation area (flammable refrigerant safety)

The minimum installation area is determined by the total refrigerant amount in the system and the installation height category.

  • A: Installation height 1.8 m or more
  • B: Installation height 0.6 m or more but less than 1.8 m
  • For ARTH09KSLAP, ARTH12KSLAP, and ARTH18KSLAP systems, typical total refrigerant charge values are at or below 1.842 kg. Where the total charge is 1.842 kg or less, there is no minimum installation area requirement (shown as “–” in manufacturer tables). Maintain good practice ventilation and ignition control regardless.

Minimum installation area reference points (text version of the table):

  • Total refrigerant amount 1.842 kg or less: Minimum installation area A = not required; Minimum installation area B = not required.
  • Total refrigerant amount 1.843 kg: Minimum installation area A = 1.40 m²; Minimum installation area B = 4.40 m².
  • Total refrigerant amount 2.000 kg: Minimum installation area A = 1.63 m²; Minimum installation area B = 5.09 m².
  • Total refrigerant amount 2.200 kg: Minimum installation area A = 1.88 m²; Minimum installation area B = 5.88 m².
  • Total refrigerant amount 2.400 kg: Minimum installation area A = 2.14 m²; Minimum installation area B = 6.70 m².
  • Total refrigerant amount 2.600 kg: Minimum installation area A = 2.42 m²; Minimum installation area B = 7.57 m².
  • Total refrigerant amount 2.800 kg: Minimum installation area A = 2.71 m²; Minimum installation area B = 8.46 m².
  • Total refrigerant amount 3.000 kg: Minimum installation area A = 3.01 m²; Minimum installation area B = 9.39 m².
  • Total refrigerant amount 3.200 kg: Minimum installation area A = 3.32 m²; Minimum installation area B = 10.35 m².
  • Total refrigerant amount 3.400 kg: Minimum installation area A = 3.64 m²; Minimum installation area B = 11.34 m².
  • Total refrigerant amount 3.600 kg: Minimum installation area A = 3.98 m²; Minimum installation area B = 12.35 m².
  • Total refrigerant amount 3.800 kg: Minimum installation area A = 4.32 m²; Minimum installation area B = 13.40 m².
  • Total refrigerant amount 4.000 kg: Minimum installation area A = 4.68 m²; Minimum installation area B = 14.47 m².
  • Total refrigerant amount 4.200 kg: Minimum installation area A = 5.04 m²; Minimum installation area B = 15.57 m².
  • Total refrigerant amount 4.400 kg: Minimum installation area A = 5.42 m²; Minimum installation area B = 16.69 m².
  • Total refrigerant amount 4.600 kg: Minimum installation area A = 5.80 m²; Minimum installation area B = 17.83 m².
  • Total refrigerant amount 4.800 kg: Minimum installation area A = 6.20 m²; Minimum installation area B = 19.00 m².
  • Total refrigerant amount 5.000 kg: Minimum installation area A = 6.60 m²; Minimum installation area B = 20.19 m².
  • Total refrigerant amount 5.200 kg: Minimum installation area A = 7.01 m²; Minimum installation area B = 21.40 m².
  • Total refrigerant amount 5.400 kg: Minimum installation area A = 7.43 m²; Minimum installation area B = 22.63 m².
  • Total refrigerant amount 5.600 kg: Minimum installation area A = 7.85 m²; Minimum installation area B = 23.87 m².
  • Total refrigerant amount 5.800 kg: Minimum installation area A = 8.28 m²; Minimum installation area B = 25.13 m².

3) Tools and materials (R32/R410A rated)

  • High-pressure gauge manifold suitable for R32/R410A (high-side rated accordingly)
  • R32/R410A charging hoses (correct pressure rating)
  • Vacuum pump and appropriate adapters (avoid series motor type vacuum pumps where prohibited)
  • R32/R410A compatible leak detector (flammable refrigerant suitable)
  • Tube cutter, deburr tool, flare tool suitable for R32/R410A, torque wrenches for flare nuts and caps
  • Nitrogen cylinder + regulator for pressure testing
  • Electronic refrigerant charging scale (recommended for accurate additional charging)
  • Insulation suitable for both liquid and gas lines

4) System overview (power, control, commissioning flow)

  • Power architecture: Outdoor unit is mains-powered. Indoor unit is supplied via the indoor–outdoor connection cable (do not separately power the indoor unit unless explicitly specified for a different system).
  • Control: Indoor unit supports Wired Remote Controller or Wireless Remote Controller options (job dependent). Function settings may be performed via Wired Remote Controller or Wireless Remote Controller (optional equipment).
  • Recommended workflow: Install (mechanical) → electrical → pressure test → evacuation → open service valves → add charge (if required) → function settings (static pressure / control) → test run → handover.

5) Refrigerant piping requirements (pipe sizes and lengths)

5.1 Copper pipe material and minimum wall thickness (R32/R410A)

  • Use seamless phosphor deoxidised copper.
  • Do not use existing piping where contamination, moisture, or incompatible oils/materials may exist.

Minimum wall thickness (annealed copper) by pipe outside diameter:

  • 6.35 mm outside diameter (nominal size 1/4"): minimum thickness 0.80 mm
  • 9.52 mm outside diameter (nominal size 3/8"): minimum thickness 0.80 mm
  • 12.70 mm outside diameter (nominal size 1/2"): minimum thickness 0.80 mm

5.2 Refrigerant pipe connection sizes by indoor unit model (liquid and gas)

Use the indoor unit model number below to identify the correct liquid pipe size and gas pipe size:

  • ARTH09KSLAP: Liquid pipe size 6.35 mm (1/4"); Gas pipe size 9.52 mm (3/8")
  • ARTH12KSLAP: Liquid pipe size 6.35 mm (1/4"); Gas pipe size 9.52 mm (3/8")
  • ARTH18KSLAP: Liquid pipe size 6.35 mm (1/4"); Gas pipe size 12.70 mm (1/2")
  • Insulate both liquid and gas lines. Increase insulation thickness where condensation risk exists (high humidity / low return air temperature).
  • Keep pipe ends capped/sealed until final brazing/flaring to prevent moisture ingress.

5.3 System piping limits (piping length, height difference, factory pre-charge, and additional charge rate)

Piping limits and charging parameters by outdoor unit model:

  • AOTH09KBTA: Maximum piping length 20 m; Maximum height difference 15 m; Factory pre-charge piping length 15 m; Additional charge rate 20 g per metre beyond 15 m.
  • AOTH12KBTA: Maximum piping length 20 m; Maximum height difference 15 m; Factory pre-charge piping length 15 m; Additional charge rate 20 g per metre beyond 15 m.
  • AOTH18KBTA: Maximum piping length 30 m; Maximum height difference 20 m; Factory pre-charge piping length 20 m; Additional charge rate 20 g per metre beyond 20 m.

6) Electrical requirements

6.1 Outdoor unit supply (mains)

  • Use a dedicated circuit and isolator in accordance with local regulations.
  • Provide earth leakage protection (RCD/ELCB) as required by local standards.
  • Use cable sizes that maintain voltage drop within acceptable limits; upsize conductors where run length demands.

Outdoor unit electrical requirements by model (text version of the table):

  • AOTH09KBTA: Supply Single phase 240 V; Minimum power supply cable 1.5 mm² (2 core + earth); Breaker or fuse reference 10 A; Earth leakage protection reference 30 mA.
  • AOTH12KBTA: Supply Single phase 240 V; Minimum power supply cable 1.5 mm² (2 core + earth); Breaker or fuse reference 16 A; Earth leakage protection reference 30 mA.
  • AOTH18KBTA: Supply Single phase 240 V; Minimum power supply cable 1.5 mm² (2 core + earth); Breaker or fuse reference 16 A; Earth leakage protection reference 30 mA.

6.2 Indoor to outdoor connection cable (power + communication)

  • Indoor unit is powered from the outdoor unit via the connection cable.
  • Minimum conductor size: 1.5 mm² (type equivalent to 60245 IEC57 or local equivalent), 3 conductors + earth.
  • Do not bundle the connection cable with remote controller cable (risk of erroneous operation).

6.3 Remote controller cable (wired controller option)

  • Use the specified remote controller cable type/size per controller documentation.
  • Remote controller bus maximum length (total): A + B + C + D + E is 500 m or less (multi-drop wiring where applicable).
  • Multiple remote control: up to 2 remote controllers can operate one indoor unit (Primary/Secondary). Timer and self-diagnosis functions may be restricted on secondary units.

6.4 External input and output (indoor unit terminals)

External input

  • Indoor unit functions such as Operation/Stop or Forced stop can be controlled via indoor unit terminals.
  • Input cable: twisted pair (22 AWG). Maximum length: 150 m.
  • Wire routing must be separate from power cable line.
  • Mode selection is via indoor function setting (Function No. 46).

External output

  • Output cable: twisted pair (22 AWG). Maximum length: 25 m.
  • Output voltage: Hi DC12V±2V, Lo 0V. Permissible current: 50 mA.
  • External output terminal behaviour is determined by Function No. 60.

7) Outdoor unit installation

7.1 Location and mounting

  • Install on a base that can withstand unit weight and vibration; use anchor bolts and anti-vibration measures as required.
  • Maintain required clearances for airflow and service access. Prevent discharge air recirculation.
  • Do not install where combustible gas may accumulate or in corrosive environments.
  • Secure appropriately for local wind/weather conditions.

7.2 Refrigerant piping connection (outdoor)

  • Confirm correct liquid and gas connections by pipe size and marking.
  • Use torque wrenches for flare connections to specified torques (see Section 9.1).
  • After piping, perform pressure test and evacuation before opening service valves.

8) Indoor unit installation

8.1 Site selection and serviceability

  • Install where the structure supports the unit mass and minimises vibration transmission.
  • Ensure access for filter service, electrical service, refrigerant piping connections, and drain servicing after installation.
  • Do not install where oil mist, corrosive gas, or significant dust may affect performance without appropriate mitigation.

8.2 Ductwork and airflow management (critical)

  • Confirm duct design external static pressure (ESP) aligns with unit capability and the selected static pressure setting.
  • Seal duct joints to prevent air leakage and performance degradation.
  • Confirm return air path and filter arrangement prevents debris ingress to the fan/coil.

8.3 Condensate drain

  • Provide correct fall and trapping per local best practice to prevent blow-off and odours.
  • Insulate drain piping where sweating may occur.
  • Water-test drainage prior to ceiling closure / handover.

8.4 DIP switch 101 (indoor unit)

DIP switch settings (text version of the table):

  • DIP switch 1: ON = Disable; OFF = Enable (Factory); Details = Drainage function setting.
  • DIP switch 2: ON = Enable (Factory); OFF = Disable; Details = Auto louver grille setting.
  • DIP switch 3: ON = Enable (Factory); OFF = Disable; Details = Fan delay setting (aux heater use case).

9) Pressure test, evacuation, commissioning

9.1 Flare work – tightening torques (system)

Flare nut tightening torque by pipe size (text version of the table):

  • 1/4" pipe size (outside diameter 6.35 mm): 16–18 N·m
  • 3/8" pipe size (outside diameter 9.52 mm): 32–42 N·m
  • 1/2" pipe size (outside diameter 12.70 mm): 49–61 N·m

9.2 Leak test (air tightness test)

  • Perform an air tightness test using nitrogen while all outdoor unit valves are closed.
  • Reference test pressure: 4.15 MPa (confirm job-specific limits and ensure safe practices are followed).
  • Confirm all joints are leak-free prior to evacuation.

9.3 Vacuum evacuation

  • Evacuate to –0.1 MPa (–76 cmHg).
  • When –0.1 MPa is reached, operate the vacuum pump for at least 15 minutes.
  • After evacuation, close manifold valves, stop pump, and confirm vacuum stability (no rise). If vacuum rises, address leaks/moisture and repeat.
  • Disconnect hoses, then open service valves fully and refit caps to specified torques.

9.4 Service valve / port cap torques (outdoor reference)

Service valve and charging port cap tightening torques (text version of the table):

  • Blank cap (applicable sizes 1/4" and 3/8"): 20–25 N·m
  • Blank cap (applicable size 1/2"): 28–32 N·m
  • Charging port cap (R32/R410A): 12.5–16 N·m

10) Additional refrigerant charging

  • Factory charge includes refrigerant suitable for the pre-charge piping length shown below.
  • Additional charge rate: 20 g per metre beyond the factory pre-charge length.
  • Record factory charge, additional charge, and total charge on the outdoor unit refrigerant label.
  • Charge R32 as required using appropriate safety procedures (flammable refrigerant) and accurate weighing (electronic scale recommended).

10.1 Factory pre-charge length and maximum charge by outdoor model

  • AOTH09KBTA: Factory pre-charge piping length 15 m; Factory charge reference 850 g; Maximum additional charge 100 g; Maximum total charge 950 g.
  • AOTH12KBTA: Factory pre-charge piping length 15 m; Factory charge reference 850 g; Maximum additional charge 100 g; Maximum total charge 950 g.
  • AOTH18KBTA: Factory pre-charge piping length 20 m; Factory charge reference 1020 g; Maximum additional charge 200 g; Maximum total charge 1220 g.

10.2 Additional charge calculation

  • Formula: Additional charge (g) = (Actual piping length – Pre-charge length) × 20 g per metre
  • If actual piping length is less than or equal to the pre-charge length, no additional charge is required.

10.3 Worked examples (quick reference)

  • AOTH09KBTA or AOTH12KBTA: 15 m total piping length = 0 g additional charge; 20 m total piping length = 100 g additional charge.
  • AOTH18KBTA: 20 m total piping length = 0 g additional charge; 25 m total piping length = 100 g additional charge; 30 m total piping length = 200 g additional charge.

11) Indoor function settings

Function setting can be performed with the Wired Remote Controller or Wireless Remote Controller (remote controller is optional equipment). Refer to the applicable remote controller documentation for detailed setting operations.

11.1 Function settings (ARTH09KSLAP, ARTH12KSLAP, ARTH18KSLAP)

Function 11 – Filter sign

  • Function 11, Setting value 00: Standard (400 hours).
  • Function 11, Setting value 01: Long interval (1000 hours).
  • Function 11, Setting value 02: Short interval (200 hours).
  • Function 11, Setting value 03: No indication (Factory).

Function 26 – Static pressure

  • Set the required external static pressure to match the duct design.
  • Static pressure range differs by indoor unit model:
    • ARTH09KSLAP: 0 to 30 Pa
    • ARTH12KSLAP: 0 to 30 Pa
    • ARTH18KSLAP: 0 to 50 Pa

Function 26 settings (text version of the table):

  • Function 26, Setting value 00: 0 Pa
  • Function 26, Setting value 01: 10 Pa
  • Function 26, Setting value 02: 20 Pa
  • Function 26, Setting value 03: 30 Pa
  • Function 26, Setting value 04: 40 Pa
  • Function 26, Setting value 05: 50 Pa
  • Function 26, Setting value 31: Standard setting (Factory): 10 Pa for ARTH09KSLAP and ARTH12KSLAP; 15 Pa for ARTH18KSLAP.

Function 30 and Function 31 – Room temperature control for indoor unit sensor

  • Applies correction to the indoor unit room temperature sensor for cooling and heating control.
  • Temperature correction values show the difference from the manufacturer recommended Standard setting (Setting value 00).

Function 30 (Cooling) and Function 31 (Heating) settings (text version of the table):

  • Function 30 / Function 31, Setting value 00: Standard setting (Factory)
  • Function 30 / Function 31, Setting value 01: No correction 0.0°C (0°F)
  • Function 30 / Function 31, Setting value 02: −0.5°C (−1°F)
  • Function 30 / Function 31, Setting value 03: −1.0°C (−2°F)
  • Function 30 / Function 31, Setting value 04: −1.5°C (−3°F)
  • Function 30 / Function 31, Setting value 05: −2.0°C (−4°F)
  • Function 30 / Function 31, Setting value 06: −2.5°C (−5°F)
  • Function 30 / Function 31, Setting value 07: −3.0°C (−6°F)
  • Function 30 / Function 31, Setting value 08: −3.5°C (−7°F)
  • Function 30 / Function 31, Setting value 09: −4.0°C (−8°F)
  • Function 30 / Function 31, Setting value 10: +0.5°C (+1°F)
  • Function 30 / Function 31, Setting value 11: +1.0°C (+2°F)
  • Function 30 / Function 31, Setting value 12: +1.5°C (+3°F)
  • Function 30 / Function 31, Setting value 13: +2.0°C (+4°F)
  • Function 30 / Function 31, Setting value 14: +2.5°C (+5°F)
  • Function 30 / Function 31, Setting value 15: +3.0°C (+6°F)
  • Function 30 / Function 31, Setting value 16: +3.5°C (+7°F)
  • Function 30 / Function 31, Setting value 17: +4.0°C (+8°F)

Function 35 and Function 36 – Room temperature control for wired remote controller sensor

  • Applies correction to the wired remote controller temperature sensor (when used).
  • To change this setting, set Function 42 to Both (Setting value 01) and enable the remote controller thermo sensor (Thermo Sensor icon displayed).

Function 35 (Cooling) and Function 36 (Heating) settings (text version of the table):

  • Function 35 / Function 36, Setting value 00: No correction (Factory)
  • Function 35 / Function 36, Setting value 01: No correction 0.0°C (0°F)
  • Function 35 / Function 36, Setting value 02: −0.5°C (−1°F)
  • Function 35 / Function 36, Setting value 03: −1.0°C (−2°F)
  • Function 35 / Function 36, Setting value 04: −1.5°C (−3°F)
  • Function 35 / Function 36, Setting value 05: −2.0°C (−4°F)
  • Function 35 / Function 36, Setting value 06: −2.5°C (−5°F)
  • Function 35 / Function 36, Setting value 07: −3.0°C (−6°F)
  • Function 35 / Function 36, Setting value 08: −3.5°C (−7°F)
  • Function 35 / Function 36, Setting value 09: −4.0°C (−8°F)
  • Function 35 / Function 36, Setting value 10: +0.5°C (+1°F)
  • Function 35 / Function 36, Setting value 11: +1.0°C (+2°F)
  • Function 35 / Function 36, Setting value 12: +1.5°C (+3°F)
  • Function 35 / Function 36, Setting value 13: +2.0°C (+4°F)
  • Function 35 / Function 36, Setting value 14: +2.5°C (+5°F)
  • Function 35 / Function 36, Setting value 15: +3.0°C (+6°F)
  • Function 35 / Function 36, Setting value 16: +3.5°C (+7°F)
  • Function 35 / Function 36, Setting value 17: +4.0°C (+8°F)

Function 40 – Auto restart

  • Function 40, Setting value 00: Enable (Factory)
  • Function 40, Setting value 01: Disable
  • Auto restart is an emergency function (for example, power outage). Do not use in normal operation. Operate the unit by remote controller or external device.

Function 42 – Room temperature sensor switching (wired remote controller)

  • Function 42, Setting value 00: Indoor unit (Factory)
  • Function 42, Setting value 01: Both (Indoor unit + wired remote controller)

Function 44 – Remote controller custom code (wireless remote controller)

  • Function 44, Setting value 00: A (Factory)
  • Function 44, Setting value 01: B
  • Function 44, Setting value 02: C
  • Function 44, Setting value 03: D

Function 46 – External input control

  • Function 46, Setting value 00: Operation/Stop mode 1 (Factory)
  • Function 46, Setting value 01: Setting prohibited
  • Function 46, Setting value 02: Forced stop mode
  • Function 46, Setting value 03: Operation/Stop mode 2

Function 48 – Room temperature sensor switching (Aux.)

  • To use the wired remote controller temperature sensor only, change to Wired Remote Controller (Setting value 01).
  • This function operates only if Function 42 is set to Both (Setting value 01).
  • Function 48, Setting value 00: Both (Factory)
  • Function 48, Setting value 01: Wired Remote Controller

Function 49 – Indoor unit fan control for energy saving for cooling

  • Function 49, Setting value 00: Disable (fan operates continuously according to remote controller setting when outdoor unit is stopped)
  • Function 49, Setting value 01: Enable (fan operates intermittently at very low speed when outdoor unit is stopped)
  • Function 49, Setting value 02: Remote controller (Factory) (enable or disable via remote controller where supported)

Function 60 – Switching functions for external output terminal

  • Function 60, Setting value 00: Operation status (Factory)
  • Function 60, Setting value 09: Error status
  • Function 60, Setting value 10: Fresh air control
  • Function 60, Setting value 11: Auxiliary heater

External output operation behaviour (text version of the table):

  • Function 60 setting value 00 (Operation status): Stop = 0 V; Operation = DC 12 V.
  • Function 60 setting value 09 (Error status): Normal = 0 V; Error = DC 12 V.
  • Function 60 setting value 10 (Fresh air control): Indoor unit fan stop = 0 V; Indoor unit fan operation = DC 12 V.
  • Function 60 setting value 11 (Auxiliary heater): External heater OFF = 0 V; External heater ON = DC 12 V.

11.2 Setting record (recommended)

Record any changes to the settings for commissioning traceability.

Setting record template (text version of the table):

  • Function 11: Filter sign – Setting value: ________
  • Function 26: Static pressure – Setting value: ________
  • Function 30: Room temperature control for indoor unit sensor (Cooling) – Setting value: ________
  • Function 31: Room temperature control for indoor unit sensor (Heating) – Setting value: ________
  • Function 35: Room temperature control for wired remote controller sensor (Cooling) – Setting value: ________
  • Function 36: Room temperature control for wired remote controller sensor (Heating) – Setting value: ________
  • Function 40: Auto restart – Setting value: ________
  • Function 42: Room temperature sensor switching – Setting value: ________
  • Function 44: Remote controller custom code – Setting value: ________
  • Function 46: External input control – Setting value: ________
  • Function 48: Room temperature sensor switching (Aux.) – Setting value: ________
  • Function 49: Indoor unit fan control for energy saving for cooling – Setting value: ________
  • Function 60: Switching functions for external output terminal – Setting value: ________

12) Test run and handover

12.1 Pre-start validation

  • All covers fitted, wiring secured with clamps, and cable outlets sealed (condensation/insect prevention).
  • Refrigerant piping: leak test and evacuation complete, service valves opened fully, caps torqued.
  • Drainage proven via water test (no leaks, correct fall).
  • Airflow verified and duct system balanced; static pressure setting matches design intent.

12.2 Operational checks

  • Controller operation and display status normal (no fault codes).
  • Indoor fan operation stable (no hunting / abnormal ramping).
  • Cooling and heating response normal (where seasonal conditions permit).
  • No abnormal noise, vibration, or water leakage.
  • No refrigerant leakage detected.

12.3 Customer guidance

  • Explain controller operation, setpoints, timers and schedules (where applicable).
  • Explain filter access, cleaning intervals and service requirements.
  • Confirm any external interlocks (operation/stop input, forced stop, fresh air control, auxiliary heater interlock) where installed.

13) Pump down (forced cooling operation)

  • Pump down is used for system relocation or disposal refrigerant recovery in accordance with manufacturer procedure and local regulatory requirements.
  • Initiate forced cooling or test run mode per the outdoor unit procedure or controller guidance (method varies by controller and outdoor printed circuit board).
  • Close the 2-way (liquid) valve fully during forced cooling operation, then close the 3-way (gas) valve after the required run period and stop operation.
  • Do not proceed if refrigerant is depleted due to damaged piping; confirm leak-free condition first.

14) Error codes (indoor/outdoor consolidated)

Error codes may be displayed on a wired controller, or indicated via indoor LED blink patterns. Capture the code, confirm wiring and communication integrity, and apply a standard diagnostic workflow (power integrity, wiring polarity and termination, printed circuit board connections, sensors, fan motors, refrigerant circuit, and outdoor system checks).

Error code list (one-line format):

  • 11 – Serial communication error
  • 12 – Wired remote controller communication error
  • 19 – Indoor unit capacity / model information error (system dependent)
  • 1A – Combination error (indoor unit and outdoor unit mismatch)
  • 1C – Connection unit number / configuration error
  • 1D – Indoor unit address / setting error (system dependent)
  • 1E – Outdoor unit address / setting error (system dependent)
  • 20 – Unit number / address setting error (system dependent)
  • 21 – Unit number / address setting error (system dependent)
  • 22 – Indoor unit capacity / model information error
  • 23 – Combination error
  • 24 – Connection unit number error
  • 26 – Indoor unit address setting error
  • 27 – Outdoor unit address setting error
  • 29 – Connection unit number error (system dependent)
  • 31 – Indoor unit printed circuit board error
  • 32 – Indoor unit fan motor 1 error
  • 33 – Indoor unit coil (liquid) thermistor error
  • 35 – Indoor unit heat exchanger thermistor error
  • 39 – Indoor unit other thermistor error
  • 3A – Indoor unit fan motor 2 error (where applicable)
  • 41 – Outdoor unit discharge temperature thermistor error
  • 42 – Outdoor unit heat exchanger temperature thermistor error
  • 44 – Outdoor unit air temperature thermistor error
  • 46 – Outdoor unit pressure sensor error (where applicable)
  • 49 – Outdoor unit fan motor error
  • 51 – Indoor unit fan motor error
  • 53 – Drain pump error (where applicable)
  • 54 – Electric air cleaner / accessory error (where applicable)
  • 55 – Filter sign / filter setting error
  • 57 – Damper error (where applicable)
  • 58 – Intake grille error (where applicable)
  • 59 – Indoor unit fan motor 2 error
  • 5A – Indoor unit fan motor 3 error (where applicable)
  • 5U – Indoor unit error (general)
  • 61 – Outdoor unit printed circuit board error
  • 62 – Outdoor unit fan motor error
  • 63 – Outdoor unit compressor error
  • 64 – Outdoor unit discharge temperature error
  • 65 – Outdoor unit high pressure protection / abnormal pressure
  • 68 – Outdoor unit low pressure / refrigerant shortage protection (system dependent)
  • 6A – Outdoor unit power transistor / IPM error
  • 71 – Outdoor unit EEPROM / parameter error
  • 72 – Outdoor unit communication error (system dependent)
  • 73 – Outdoor unit inverter error
  • 74 – Outdoor unit fan control error
  • 75 – Outdoor unit sensor error (general)
  • 76 – Outdoor unit discharge superheat / control abnormal
  • 77 – Outdoor unit actuator / valve error (where applicable)
  • 82 – Outdoor unit overcurrent protection
  • 83 – Outdoor unit compressor lock / start failure
  • 84 – Outdoor unit abnormal power supply (voltage)
  • 86 – Outdoor unit abnormal refrigerant circuit (system dependent)
  • 94 – Outdoor unit discharge temperature abnormal (protective)
  • 95 – Outdoor unit high pressure abnormal (protective)
  • 97 – Outdoor unit low pressure / shortage (protective)
  • 98 – Outdoor unit abnormal sensor signal (protective)
  • 99 – Outdoor unit abnormal communication (protective)
  • 9A – Outdoor unit abnormal operation (protective)
  • A1 – Discharge temperature error
  • A3 – High pressure switch / pressure error (where applicable)
  • A4 – External temperature thermistor error (where applicable)
  • A5 – Outdoor unit heat exchanger temperature error
  • AC – Heat sink temperature error
  • J2 – Branch / peripheral communication error (system dependent)

15) UTY-RNRT specific error displays

This section applies only where a UTY-RNRT wired controller is installed. Display formats may differ from indoor LED blink patterns.

UTY-RNRT display codes (text version of the table):

  • CC.1 – Wired remote controller communication error
  • C2.1 – Serial communication error
  • 12.1 – Remote controller to indoor unit communication error
  • 12.3 – Remote controller power supply abnormal
  • 12.4 – Remote controller printed circuit board / internal error
  • 26.4 – Indoor unit address / setting error (system dependent)
  • 26.5 – Outdoor unit address / setting error (system dependent)
  • 15.4 – Check run / commissioning incomplete (system dependent)